Shampoo containing amine oxide



United States Patent 3,086,943 SHAMPOO CONTAINING AMENE OXIDE Edward William Lang, Hamilton County, Ohio, assignor to The Procter & Gamble Company, Cincinnati, Ohio, a corporation of Ohio No Drawing. Filed June 10, 1959, Ser. No. 819,247 12 Claims. (Cl. 252-152) The shampoo of this invention contains amine oxide and anionic detergent. In addition to cleaning the hair and producing copious suds, use of the shampoo reduces the static electrification of dry hair on combing or brushing and increases its manageability.

A shampoo which thoroughly cleans the hair, removlng much of its natural oil, leave the hair in such a condition after drying that combing produces static electrification of the hair fibers. Especially in dry air, the hair fibers repel each other giving the hair an unkempt, fuzzy, flighty appearance. This effect is often spoken of as hair fly for brevity and convenience. While the static charge will slowly dissipate from the hair fibers, recomb-ing will cause the same diificulty to arise again.

If the shampoo preparation is designed to preserve much of the natural oil in the hair, the criticism can be voiced that it does an incomplete cleaning job. Some shampoos attempt to solve this problem by using a highly effective detergent and a hair conditioning agent which serves as a replacement for the oil removed from the hair. Examples of such hair conditioning agents are polyglycols, fatty acid esters of glycols, natural or synthetic waxes, and lanolin derivatives. Use of formulations containing excessive amounts of hair conditioning agents of the oily type may cause the hair to have an unpleasant oily appearance and feel. Formulations containing certain hair conditioning agents suffer from the aditional difficulty that the oily material inhibits sudsing of the shampoo. Most people have come to expect copious lather from their shampoo and are dissatisfied if it is not formed.

Among the objects of this invention are: (1) to provide a homogeneous shampoo which produces a copious lather, effectively cleans the hair, leaves the hair in a lustrous condition and additionally (2) to provide a shampoo which leaves the shampooed hair after drying in a manageable condition such that static electrification caused by combing or brushing is reduced or eliminated.

These andother objects are achieved by formulations containing specified amine oxides and detergents with intermediate linkages, including in this class ampholytic detergents, at pH values of from about 6.5 to about 8.5.

A general view of this invention, without as yet defining terms, is presented before proceeding with a full disclosure, including definitions, and specific examples. Amine oxide is the ingredient which has the primary effect in reducing the static electrification of hair, and it is more effective at relatively low pH values of about 6.5 to about 8.5 than at higher pH values. Although it has sudsing and detergent properties, it is not suitable as the sole surface active ingredient of a shampoo. It should be combined with an anionic detergent to improve lather and mildness, and to lower cost. However, amine oxide and many conventional anionic detergents are incompatible, that is, do not form homogeneous solutions free from a precipitate of these components at these low pH values. Certain detergents characterized by an intermediate link are compatible in specified composition ranges. These detergents with intermediate links can be ampholytic or anionic detergents. Amine oxide can be combined with an ampholytic detergent or an anionic detergent with an intermediate linkage or with both. When the detergent with an intermediate link which is combined with amine oxide is an ampholytic detergent, anionic detergents without 3,086,943 Patented Apr. 23, 1963 "ice intermediate links can also be dissolved in the shampoo formulation.

In the following disclosure of the invention, percentages refer to weight percent of the total formula unless otherwise indicated.

Amine oxides are nonionic compounds of the general formula R R R N O. The arrow is a conventional representation of a semipolar bond. They are generally prepared by the direct oxidation of the appropriate tertiary amine. When R is a much longer chain than R and R amine oxides have surface activity. For the purpose of this invention R is an alkyl radical of from 10 to 16 carbon atoms. Desirable surface active and fly reducing properties are lost if R is substantially less than 10 carbon atoms, and solubility in the present formulation is too low if R is greater than 16 carbon atoms. R and R are each selected from the group consisting of methyl and ethyl radicals. Preferably R is a dodecyl radical or a mixture of dodecyl with decyl, tetradecyl and hexadecyl radicals such that at least 50% of the radicals are dodecyl radicals. R and R are preferably methyl radicals. The amine oxide will be used at from about 2% to about 15% of the total formula, preferably at from about 5% to about 10%. Too little amine oxide does not contribute sufiicient sudsing and hair control performance to the formulations. Too much amine oxide interferes with putting a sufiicient amount of anionic detergent in the formula while maintaining it as .a homogeneous liquid.

As the pH of the shampoo formulations of this invention is decreased, the static electrification caused by combing or brushing dried shampooed hair is decreased. In other words, hair fly is decreased. Below about pH 8.5 the decrease in static electrification is significant; pH values of about 8 or lower are preferred for the decrease is greater. The pH is maintained above about 6.5 and high enough to keep the amine oxide and anionic detergent compatible. At too low a pH the amine oxide and anionic detergent interact to form a precipitate. A week acid such as citric acid is preferably used, because of its buffering effect, if it is necessary to lower the pH of the formula. Less than about 2% is employed. Other common acids can be employed. The minimum pH at which compatibility is maintained is, of course, affected by the concentrations and proportions of amine oxide and anionic detergent.

At pH values of above about 9" most anionic detergents are compatible with amine oxides in a homogeneous solution free from a precipitate. However, control of hair fly, an important benefit of this invention, is largely lost at such high pH values. It has been discovered that the compatibility problem experienced within the desirable pH range of 6.5 to 8.5 can be overcome by using a watersoluble detergent with an intermediate linkage. By this is meant detergents of the general formula, RZXM. R is an acyclic hydrophobic group containing from about 8 to about 18 carbon atoms; X is an anion selected from the group consisting of SO OSO and COO'=; Z is an intermediate group joined to R by a member of the group consisting of ether, polyether, ester, amide and amine linkages having some polar character derived from nitro-/ gen and/or oxygen atoms; and M is a cation to neutralize the charge of the anion. Classification according to, whether the detergent has an intermediate linkage or not is used in Surface Active Agents and Detergents, by A. M. Schwartz, J. W. Perry, and J. Berch, Interscience Publishers, New York, 1958, vol. II.

The compatible detergents can be subdivided according to whether the intermediate linkage, Z, contains a basic nitrogen, or not, i.e., whether the detergent is an ampholytic detergent or not. A secondary or tertiary nitrogen is considered a basic nitrogen but a quaternary nitrogen, an amide nitrogen, or a substituted amide nitrogen is not.

Detergents with intermediate links illustrative of the types suitable for use in the formulations of this invention include those listed in the following groups I and II. Additional ampholytic detergents suitable for use in this invention are included in those disclosed in Schwartz et al., as cited above, on pages 138444. R and M have the same meaning as before; R'C, in an acylradical, .has the same number of carbonatoms as R.

I. ANIONIC Alkyl glyceryl ether sulfonate, ROCH CHOHCH SO M, including mixtures of up to 40% alkyl diglyceryl ether. Alkyl monoglyceride sulfate Fatty acid ester of isethionic acid, R'COOC H SO M. N-methyl-N-alkyl taurate, -R'CON(CH )C I-I SO M.

The alkyl polyethenoxyether sulfate where x is about 3 is an especially preferred anionic detergent with an intermediate link because of its m-ildness and excellent performance. I

II. AMPI -IOLYTIC Alkyl betaiminodipropionate, RN-(C H COOM) Alkyl beta-aminopropionate, RN(H)C H COM. A long chain imidazole derivative having the general formula N CHz CHrCHrOGHzOOOM OH CHzC O OM The detergent with an intermediate l-inkage can be selected from either group I or group II or can be a mixture of detergents selected from both groups. The total of detergent with intermediate linkage is from about to about 20%. The upper limit is to insure an adequate temperature range ofhomogeneous solution; and the lower limit is to insure an adequate contribution towards the performance of the formulation. The anionic detergent with an intermediate linkage is used atfrom 0 to about and when used as the sole intermediate linkage-containing waterrsoluble detergent, this detergent constitutes at least 5% of the total composition; but preferably it is not present in more than a two-fold weight excess over the amine oxide. Greater excesses tend to inactivate the amine oxide in its control of hair fly. The ampholytic detergent is used at from 0 to about 10%, but when used as the sole intermediate linkagecontaining water-soluble detergent, this detergent is preferably employed in a quantity of at least about 5%. A preferred combination is from about 4% to about 8% anionio detergent with about 4% to about 6% ampholytic d te n At' the pH values of formulations of this invention below 5, the most common anionic detergents are not compatible with amine oxide at the concentrations re-. quir'd. However, it has been discovered that anionic detergents other than those'with an intermediate link. can be substituted in whole or in part for the anionic detergents typified by group I so long as more than about 4% of"an'arn'pholyt-ic detergent typified by group II is: also present. The total detergent exclusive of amine oxide does not exceed about Ampholytic detergents increase the compatibility of amine oxide with (1) anionics without intermediate linkages, or (2) anionics with intermediate linkages and art R which is not acyclic. Typical examples are listed below in group III. The

ampholytic detergent, alkyl beta-iminodipropionate, is especially useful for its solubilizing-efiect; and it is the ampholytic detergent preferred for use in the formulas of this invention to solubilize detergents from group III. R, R'C and M have the same meaning as before; R" is a hydrophobic radical which is not acyclic, -i.e., which contains a cyclic group.

III. OTHER ANIONIC DETERGENTS Fatty acid soap, R'COOM Alkyl sulfate ROSO M Alkyl benzene sulfonate R"SO M Alkyl phenyl polyethenoxy sulfonate, R"(OC H SO M,

where x=1-5 Alkyl sulfonate RSOgM.

The presence of these Other Anionic Detergents is not essential in the present invention. However, one or more of them may be desirably used in special circumstances with the essential detergents containing an intermediate linkage. Use of alkyl sulfate can give especially good sudsing and is a preferred embodiment 'of this invention.

The alkyl radical, R, or the acyl'radical, RC(O)-, of the detergents preferably contains 12 carbon atoms or is a mixture of radicals containing from about 10 to about 18 carbon atoms such that at least about of the radicals contain 12 carbon atoms. Suitable mixtures are available from natural or synthetic sources. Coconut oil is a source for coconut alcohol and coconut fatty acid which have chain-lengths suitable for use in this invention. For example, typical middle cut coconut alcohol having the following composition: 2%Cm, 66%C 23 %-C and 9%C is a desirable source for alkyl radicals in-thedetergents of this invention; coconut fatty acids having the same chain length composition are a desirable source of acyl radicals. Whole cut coconut fatty acids can also be used as a source of acyl radicals; an example of the chain length distribution of such material is CrC10 15%, C12-50%, C14-17%, and C -11%. In alkyl benzene radicals, R", the alkyl radical preferably contains an average of about 8 carbon atoms.

.M,.the cation to neutralizethe charge of the anionic detergennis one which produces a water-soluble detergent salt. A variety of cations including ammonium, magnesium, and quaternary ammonium are suitable for part-icular formulas. The preferred cations for-use in the compositions of this invention are alkali metal (i.e., sodium, potassium) alkanolammonium (i.e., mono-, di-, and triethanolammonium), ammonium and mixtures thereof. Those especially preferred are sodium, potassium, 4 and triethanolammonium.

The different detergents or combinations of detergents (I, II, III, IV, V) usedwith amine oxide in the formulations of this invention are summarized in tabular form as follows:

Detergent I II III IV V With Intermediate link, RZXM:

Ampholytic X X X X Anionic X X X Other (no intermediate link or nonacyclie hydrophobe) X X or use. Among these are: up to 0.5% color, up to 1% sequestering agent to clarify solutions made from hard waters, and up to 1% perfume. Coconut diethauolamide may be added for its elfect on the feel of the hair, making it smooth but not oily feeling. None is required, but up to about can be used. Up to about 5% organic solvent for example ethyl alcohol, can be added to increase solubility or control viscosity. The water content is greater than about 60% to insure homogeneous solution over a satisfactory range of temperatures; preferably it is less than 90% to insure sufiicient active material per unit volume, and more than about 70% Example I Compositions consisting of coconut dimethylamine oxide, 10% detergent with an intermediate linkage and 80% water were prepared. Duplicate solutions except that 5% water was replaced by 5% disodium lauryl betaiminodipropionate were also prepared. The pH was adjusted up to about 9.5 and down to the value at which the solution lost its clarity, using sodium carbonate and citric acid. This minimum pH value at which the solution remained clear is noted below.

1 These cocoyl radicals have approximately the following chain length composition: 2%Ol(i, 55%-Cii, 22%O14, 0% Ciu, and 21%C1s.

1* The alkyl or acyl radical is derived from middle cut coconut alcohol or fatty acid and has approximately the following chain length composition: 2%C o, 66%O12, 23%-C14, and 9%C15.

These 12 compositions are well adapted for shampooing hair. They can be adjusted to any pH value from the minimum specified to about pH 8.5 and retain their performance. They suds and clean well, reduce the static electrification of dry shampooed hair on combing, and leave the air in a highly manageable condition.

Compositions were made up and tested as in A except that anionic detergents without intermediate linkages or with non-acyclic hydrophobic groups Were used. The results for compositions containing 5.0% disodium lauryl beta-iminodipropionate are as follows:

Triethanolammonium coconut 2 soap 7.8 Triethanolammonium coconut 1 sulfate 7.9 Sodium coconut sulfate 8.3 Sodium tert-octylphenyl triethenoxy sulfonate 7.9 Sodium alkyl sulfonate 7.5 Ammonium alkyl sulfonate 3 7.1

1 The alkyl radical is derived from middle cut coconut alcohol and has ap roxirnately the following chain len th composition: 2%- 1o, 66%-C12, 23 %C14. and 9% m.

2 Wholeeut coconut as typified by the analysis given hereinbefore.

3 The alkyl radicals are a mixture of chains containing from form clear solutions with the amine oxide at low enough pH values; for example, triethanolammonium and sodium coconut sulfate formulations without ampholytic detergent were not clear below pH 8.8-9.

Example II The following shampoo was prepared and found to be a clear homogeneous liquid at temperatures above 60 F.

Percent Dimethyl coconut 1 amine oxide 8.0 Disodium lauryl beta-iminodipropionate 5.0 Sodium coconut 1 sulfate 4.0 Coconut Z diethanolamide 1.0 Perfume 0.5 Color Less than-.. 0.01 Citric acid to adjust pH to 7.5 Water Balance Example 111 The following shampoo was prepared and proved to be a clear homogeneous liquid at temperatures above about 55 F.

Percent Dimethylcoconut 1 amine oxide 8.0 Triethanolammonium salt of sulfated condensation product of one mole of coconut 1 alcohol with about 3 moles of ethylene oxide 8.0 Coconut 1 diethanolarnide 2.0 Denatured ethyl alcohol (formula SDA 40)- 7 .0 Tetrasodium ethylenediaminetetraacetate 0.5 Perfume 0.3 Citric acid to adjust pH to 8.0. Water Balance 1 The alkyl or acyl radical is derived from middle cut coconut alcohol or fatty acid and has approximately the following Sch7ain ength composition: 2%C1o, 66%-C12, 23 %-'C14 and This shampoo gave a good suds in laboratory tests and cleaned hair effectively. It proved to be much superior to conventional shampoos in reducing static electrification of dry shampooed hair on combing and consequently greatly reduced hair fly. Hair washed with this shampoo Was left in a manageable condition. Methylethylcoconutamine oxide or diethyldodecylamine oxide can be substituted for the dimethylcoconutamine oxide in this formula Without substantially adversely afiecting the properties of performance of the formula.

EXAMPLE IV The following shampoo was prepared and proved to be a clear homogeneous liquid at temperatures above about 60 F.

Percent 'Dimethyldodecylamine oxide 7.0 Sodium salt of sulfated condensation product of one mole of coconut 1 alcohol with about 3 moles of ethylene oxide 7.0 Coconut diethanolamide 5.0 Perfume 0.2 Color Less than 0.01 Citric acid to adjust pH to 7.9.

Water Balance 'lhe alkyl radical is derived from middle cut coconut alcoholand has approximately the following chain length composition: 2%C1o, 66% C12, 23%-C14 and 9%Cm. b ZWholecut coconut typified by the analysis given hereine ore.

A and -B,--identica-l switchesof human hair (2" x 12") were washed,--(A)-withawidely distributed commercial shampooand (B) with-the shampoo -ofExam-ple II. The switches were allowedto'dry in the air after rinsing; when dried, they were untangled by combing with the coarse teeth-of a hard rubber comb. Each switch was then combed with the fine. teeth of the comb using 10 strokes. At room temperature and a relative humidity of 34% the switch washed in product (A) spread out and became disarranged .due to the repulsion of the charges built up on the hair fibers. The appearance of the switch washed in composition (B) exhibited little, if any, indication of repulsive electric charges being on the hair fibers.

What is claimed is:

1. A detergent composition especially adapted for I shampooinghair by its efiect in reducing the static electrification of combed dry hair consisting essentially of:

(a) from about 5% to about 20% of a water-soluble detergent having the formula RZXM wherein R is an acyclic hydrophobic radical containing from 8 to 18 carbon atoms, at least about 50% of said radicals containing 12 carbon atoms, X is an anion selected form the group consisting of SO 080 and COO=, Z is an intermediate linking member selected from the groupconsisting of ether, polyether, ester, amide, and amine linkages and M is a cation to neutralize the charge of the anion,

(b) from about 2% to about 15% of an amine oxide having the. general formula R 'R R N- O wherein R is an alkylradical containing from 10 to 16 carbon atomsaand R and .R .are eachselected from the group consisting of methyl and ethyl radicals, at least 50% .of theR radicalscontaininglZ carbon atoms,

and the balance substantially water,

not more than 15% of said detergent composition being ((1) wherein RZXM is anionic and not more than 10% of said detergent composition being (a) wherein the intermediate linking member contains a basic nitrogen, the

weight ratio of (b) to (11) wherein RZXM is anionic being greater than about 1 :2, the pH of said detergent composition being less than about 8.5 but high enough to give a homogeneous solution and not lower than about. 6.5.

2. The detergent composition of claim 1 wherein the water-soluble detergent RZXM is a mixture of an alkyl beta-iminodipropionate and a detergent of the formula R(OC H SO M and the cations of the said detergent are selected from the group consisting of sodium, potassium, ammonium, triethanolammonium and mixtures thereof.

3. A detergent composition especially adapted for shampooing hair by its effect in reducing the static electrification of combed hair consisting essentially of:

(a) from about 5% to about of a water-soluble detergent having the formula RZXM wherein R is an acyclic hydrophobic radical containing from 8 to 18 carbon atoms, at least 50% of said radicals containing '12 carbon atoms, 'X is an anion'selected from the group consisting of 'SO OSO and COO=, Z is an amine intermediate linking member and M is a cation to neutralize the charge of the anion.

(b) from about 2% to about of an amine oxide having the :general formula-R R R N- O wherein R is an alkyl radical containing from 10 to 16 carbon atoms and R and R3131? each selected from the group consisting of methyl and ethyl radicals, at least 50% of the R v radicals containing 12 carbon atoms, and the balancesubstantially (a) water, the pH of said detergent composition being less than about 8.5 but high enough to give a homogeneous solution and not lower than about 6.5.

4. The detergent composition of claim 3 wherein the water-solubledetergent RZXM is an alkyl beta-iminodipropionate salt of cations selected from the group consisting of sodium, potassium, ammonium triethanolammonium and mixtures thereof, and wherein R and R of the amine oxide are each methyl radicals.

5. A detergent composition especially adapted for shampooing hair by its effect in reducing the static electrification of combed hair consisting essentially of:

(a) from about 5% to about 15 of a water-soluble detergent having the formula RZXM, wherein R is an acyclic hydrophobic radical containing from 8 to 18 carbon atoms, at least 50% of said radicals containing 12 carbon atoms, X is an anion selected from the group consisting of SO OSO and COO=. Z is a polyether intermediate linking member and M is a cation to neutralize the charge of the anion.

(b) from about 2% to about 15 of an amine oxide having the general formula R R R N- O wherein R is an alkyl radical containing from 10 to 16 carbon atoms and R and R are each selected from the group consisting of methyl and ethyl radicals, at least 50% of the R radicals containing 12 carbon atoms and the balance substantially (0) water, the Weight ration of (b) 'to (a) being greater than about 1:2, the pH of said detergent composition being less than about 8.5, but high enough to give a homogeneous solution and not lower than about 6.5

6. The detergent composition of claim 5 wherein the water-soluble detergent RZXM is R OC H 50 M wherein M is selected from the group consisting of sodium, potassium, ammonium, triethanolarrunonium and mixtures thereof and wherein R and R of the amine oxide are each methyl radicals.

7. A detergent composition especially adapted for shampooing hair by its eifect in reducing static electrification of combed hair consisting essentially of:

(a) from about 5% to about'15% of a water-soluble detergent having the formula RZXM wherein R is an acyclic hydrophobic radical containing from 8 to 18 carbon atoms, at least 50% of said radicals containing 12 carbon atoms, X is an anion selected from the group consisting of SO OSO and COO=, Z is an ether intermediate linking member and M is a cation to neutralize the charge of the anion,

(b) from about 2% to about 15 of an amine oxide 'having'the general formula R R R N O wherein R is an alkyl radical containing from 10 to 16 carbon atoms and R and R are each selected from the group consisting of methyl and ethyl radicals, at least 50% of the R radicals containing 12 carbon atoms, and the balance substantially (0) water, the pH of said detergent composition being less than about 8.5 but high enough to give a homogeneous solution and not lower than about 6.5

8. A detergent composition especially adapted for shampooing hair by its efiect in reducing the static electrification of combed hair consisting essentially of:

(a) from about 5% to about 15 of a water-soluble detergent having the formula RZXM wherein R is an acyclic hydrophobic radical containing from 8 to 18 carbon atoms, at least 50% of said radicals containing 12carbon atoms, X isan anion-selected from the group consisting of SO OSO and COO=, Z is an ester intermediate linking member and M is a cation to neutralize the charge of the anion.

(b) from about 2% to about 15% of an amine oxide having the general formula R R R N O wherein R is an alkyl radical containing from 10 to 16 carbon atoms and R and R are each selected from the group consisting of methyl and ethyl radicals, at least 50% of the R radicals containing 12 carbon atoms, and the balance substantially (c) water, the pH of said detergent composition being less than about 8.5 but high enough to give a homogeneous solution and not lower than about 6.5.

9. A detergent composition especially adapted for shampooing hair by its effect in reducing the static electrification of combed hair consisting essentially of:

(a) from about 5% to about 15% of a water-soluble detergent having the formula RZXM wherein R is an acyclic hydrophobic radical containing from 8 to 18 carbon atoms, at least 50% of said radicals containing 12 carbon atoms, X is an anion selected from the group consisting of SO OSO and COO=, Z is an amide intermediate linking member and M is a cation to neutralize the charge of the anion,

(b) from about 2% to about 15% of an amine oxide having the general formula R R R N O wherein R is an alkyl radical containing from 10 to 16 carbon atoms and R and R are each selected from the group consisting of methyl and ethyl radicals, at least 50% of the R radicals containing 12 carbon atoms, and the balance substantially 1 water, the pH of said detergent composition being less than about 8.5 but high enough to give a homogeneous solution and not lower than about 6.5.

10. A detergent composition especially adapted for shampooing 'hair by its effect in reducing the static electrification of combed dry hair consisting essentially of: from about 4% to about 8% of R(OC H SO M; from about 4% to about 6% of RN(C I-I COOM) from about to about of R(CH N O; and the balance substantially water, where R is an alkyl radical containing from 10 to 16 carbon atoms, at least about 50% of R 10 containing 12 carbon atoms, and M is selected from the group consisting of ammonium, triethanolammonium, sodium, potassium, and mixtures thereof, the pH of said detergent composition being between about 7 and 8.

11. A detergent composition especially adapted for shampooing hair by its effect in reducing the static electrification of combed dry hair consisting essentially of: from about 4% to about 8% of RSO M; from about 4% to about 6% of RN(C H COOM) from about 5% to about 10% of R(CH N- O; and the balance substantially water, where R is an alkyl radical containing from 10 to 16 carbon atoms, at least about of R containing 12 carbon atoms, and M is selected from the group consisting of ammonium, triethanolammonium, sodium, potassium and mixtures thereof, the pH of said detergent composition being between about 7 and about 8.

12. A detergent composition especially adapted for shampooing hair by its etfect in reducing the static electrification of combed dry hair consisting essentially of: from about 4% to about 8% of R(OC H SO M; from about 5% to about 10% of R(CH N O; and the balance substantially water, Where R is an alkyl radical containing from 10 to 16 carbon atoms at least 50% of R containing 12 carbon atoms and M is selected from the group consisting of ammonium, triethanolammonium, sodium, potassium and mixtures thereof, the pH of said detergent composition being between about 7 and about 8.

References Cited in the file of this patent UNITED STATES PATENTS 2,060,568 Graenacher et al. Nov. 10, 1936 2,169,976 Guenther et a1. Aug. 15, 1939 2,833,722 Funderbark et al. May 6, 1958 2,874,126 Epstein et al Feb. 17, 1959 FOREIGN PATENTS 437,566 Great Britain Oct. 31, 1935 463,624 Great Britain Apr. 2, 1937 OTHER REFERENCES The Chemistry of Fatty Amines, 1948, pub. by Armour and Co., p. 13.

Schwartz and Perry: Surface Active Agents," 1949, pub. by Interscience Pub., In'c., pp. 15-17 and 7 7. 

1. A DETERGENT COMPOSITION ESPECIALLY ADAPTED FOR SHAMPOOING HAIR BY ITS EFFECT IN REDUCING THE STATIC ELECTRIFICATION OF COMBED DRY HAIR CONSISTING ESSENTIALLY OF: (A) FROM ABOUT 5% TO ABOUT 20% OF A WATER-SOLUBLE DETERGENT HAVING THE FORMULA RZXM WHEREIN T IS AN ACYCLIC HYDROPHOBIC RADICAL CONTAINING FROM 8 TO 18 CARBON ATOMS, AT LEAST ABOUT 50% OF SAID RADICALS CONTAINING 12 CARBON ATOMS, X IS AN ANION SELECTED FORM THE GROUP CONSISTING OF SO3=, OSO3= AND COO=, Z IS AN INTERMEDIATE LINKING MEMBER SELECTED FROM THE GROUP CONSISTING OF ETHER, POLYETHER, ESTER AMIDE, AND AMINE LINKAGES AND M IS A CATION TO NEUTRALIZE THE CHARGE OF THE ANION, (B) FROM ABOUT 2% TO ABOUT 15% OF AN AMINE OXIDE HAVING THE GENERAL FORMULA R1R2R3N$O WHEREIN R1 IS AN ALKYL RADICAL CONTAINING FROM 10 TO 16 CARBON ATOMS AND R2 AND R3 ARE EACH SELECTED FROM THE GROUP CONSISTING OF METHYL AND ETHYL RADICALS, AT LEAST 50% OF THE R1 RADICALS CONTAINING 12 CARBON ATOMS AND THE BALANCE SUBSTANTIALLY (C) WATER, NOT MORE THAN 15% OF SAID DETERGENT COMPOSITION BEING (A) WHEREIN RZXM IS ANIONIC AND NOT MORE THAN 10% OF SAID DETERGENT COMPOSITION BEING (A) WHEREIN THE INTERMEDIATE LINKING MEMBER CONTAINS A BASIC NITROGEN, THE WEIGHT RATIO OF (B) TO (A) WHEREIN RZXM IS ANIONIC BEING GREATER THAN ABOUT 1:2, THE PH OF SAID DETERGENT COMPOSITION BEING LESS THAN ABOUT 8.5 BUT HIGH ENOUGH TO GIVE A HOMOGENEOUS SOLUTION AND NOT LOWER THAN ABOUT 6.5 